1. Tuberaria guttata (Linnaeus) Fourreau, Ann. Soc. Linn. Lyon, N.S. 16: 340. 1868.
Cistus guttatus Linnaeus, Sp. Pl. 1: 526. 1753; Helianthemum guttatum (Linnaeus) Miller
Leaf blades elliptic to obovate (proximal) or lanceolate-linear to linear, 10–50(–75) × (2–)5–10(–18) mm, margins of distals sometimes revolute, surfaces hairy, hairs mixed: white and relatively long, white and in tufts, and red and relatively short. Pedicels 5–15 mm. Flowers: sepals 1–4 mm, villous; petals creamy yellow to yellow, usually brown to purple proximally, mostly obovate to rounded-cuneate, 4–10+ mm, apices truncate, erose to fimbrillate. Capsules 4–6 mm, villous. 2n = 36 (Europe).
Flowering Apr–May. Disturbed sites, chaparral borders, flats, oak woodlands, along streams, vernal pools; 80–200 m; introduced; Calif.; Europe; n Africa.
Nomenclatural conservation of Tuberaria against Xolantha Rafinesque rendered the name X. guttata (Linnaeus) Rafinesque incorrect for T. guttata.
Tuberaria guttata is known from the northern and central Sierra Nevada Foothills and eastern Sacramento Valley.